Home About us Contact
|
Home About us Contact | ||
|
|
||
Highly Significant Correlation (highly + significant_correlation)
Selected AbstractsThe concentrations of fatty acids in organo-mineral particle-size fractions of a ChernozemEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 3 2004G. Jandl Summary Fatty acids, the most abundant class of soil lipids, indicate pedogenetic processes and soil management. However, their quantitative distribution in organo-mineral particle-size fractions is unknown. The concentrations of n -C10:0 to n -C34:0 fatty acids both in whole soil samples and in the organo-mineral particle-size fractions of the Ap horizon of a Chernozem were determined (i) to evaluate the effects of long-term fertilization and (ii) to investigate their influence on the aggregation of organo-mineral primary particles. Quantification by gas chromatography/mass spectrometry (GC/MS) showed that long-term fertilization with nitrogen, phosphorus and potassium (NPK) and farmyard manure (FYM) led to larger concentrations (25.8 µg g,1) of fatty acids than in the unfertilized sample (22.0 µg g,1). For particle-size fractions of the unfertilized soil, the fatty acid concentrations increased from the coarse silt to the clay fractions (except for fine silt). Fertilization with NPK and FYM resulted in absolute enrichments of n -C21:0 to n -C34:0 fatty acids with a maximum at n -C28:0 in clay (×2.2), medium silt (×2.0), coarse silt (×1.8) and sand (×2.9) compared with the unfertilized treatment (the factors of enrichment are given in parentheses). New evidence for the aggregate stabilizing function of n -C21:0 to n -C34:0 fatty acids was shown by the characteristic pattern in size-fractionated, disaggregated and aggregated samples. Highly significant correlations of fatty acid concentrations with organic C concentrations and specific surface areas are interpreted as indicators of (i) trapping of fatty acids in organic matter macromolecules and (ii) direct bonding to mineral surfaces. This interpretation was supported by the thermal volatilization and determination of fatty acids by pyrolysis-field ionization mass spectrometry (Py-FIMS). [source] MRI-based evaluation of locus and extent of neurotoxic lesions in monkeys ,HIPPOCAMPUS, Issue 4 2001e Málková Abstract To minimize the variability in the extent of lesions made by injections of the excitotoxin ibotenic acid in rhesus monkeys, we developed and validated an MRI-based method to determine the efficacy of the injections soon after surgery. T2-weighted MR images were obtained 6,11 days after surgery from 17 brain hemispheres of monkeys that had received bilateral lesions of either the hippocampal formation (HF), perirhinal cortex, or parahippocampal cortex. The extent of lesion estimated from the hypersignal that appeared in and outside of the targeted area on these MR images was compared with the extent of damage assessed histologically after survival periods ranging from 120,370 days. Highly significant correlations (r values between 0.85,0.99) were found between these two measures for several regions in the medial temporal lobe. Based on this finding, lack of hypersignal in the targeted area of some Ss was followed by successful reinjection of the neurotoxin to create more complete cell loss prior to the postoperative phase of the study. We also assessed the relationship between a postoperative reduction in HF volume, measured from T1-weighted MR images, and the extent of damage determined histologically in 14 hemispheres of monkeys with bilateral excitotoxic HF lesions. The HF volume decreases sharply after surgery until 40,50 days postoperatively, after which there is only a minor further decrease. Based on this finding, we obtained T1-weighted MR images at least 44 days but in most cases close to 1 year after surgery. A highly significant positive correlation (r = 0.95, P < 0.001) was found between neuronal damage and volume reduction, with nearly complete neuronal damage (96,99%) corresponding to a volume reduction of 68,79%. These MRI-based methods thus provide an accurate in vivo evaluation of the locus and extent of neurotoxic lesions. Application of these methods can ensure that each animal in the experiment is used effectively. Hippocampus 2001;11:361,370. Published 2001 Wiley-Liss, Inc. [source] Proteolysis and texture changes of a Spanish soft cheese (,Torta del Casar') manufactured with raw ewe milk and vegetable rennet during ripeningINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 3 2010Delgado Francisco-José Summary Proteolysis and textural changes of the Spanish ewe raw milk soft cheese of the Protected Designation of Origin Torta del Casar were studied in four different stages of ripening, with 1, 30, 60 and 90 days. In general, proteolysis in Torta del Casar cheese was weak at 1 and 30 days and it was more intense between the 30,60 days of ripening. Soluble nitrogen non-protein nitrogen, polypeptide N and free amino acids values significantly increased during cheese ripening. Protein and casein nitrogen decreased significantly after 60 days of ripening resulting in the increase of the other nitrogen fractions measured. Caseins changes determined by capillary zone electrophoresis showed that proteolysis of ,-casein occurred faster than ,s1-casein but the latter suffered higher proteolytic degradation at the end of ripening (day 90). This pattern of degradation of caseins is reversed in other cheeses made with animal rennet. Texture analysis showed that firmness and consistency decreased along ripening while adhesiveness increased. Highly significant correlations were found between textural parameters, residual caseins levels and nitrogen fractions during maturation, which shows the importance of proteolytic changes for an optimal texture formation. [source] Fatty Acid Ethyl Esters in Meconium: Are They Biomarkers of Fetal Alcohol Exposure and Effect?ALCOHOLISM, Issue 7 2006Enrique M. Ostrea Jr. Background: Biomarkers of fetal exposure to alcohol are important to establish so that early detection and intervention can be made on these infants to prevent undesirable outcomes. The aim of this study was to analyze long-chain fatty acid ethyl esters (FAEEs) in meconium as potential biomarkers of fetal alcohol exposure and effect. Methods: Fatty acid ethyl esters were analyzed in the meconium of 124 singleton infants by positive chemical ionization gas chromatography/mass spectrometry (GC/MS) and correlated to maternal ethanol use. Results: A total of 124 mother/infant dyads were enrolled in the study: 31 were in the control group and 93 were in the alcohol-exposed group. The incidence (28% vs 9.7%, p=0.037) of ethyl linoleate detected in meconium was significantly higher in the alcohol-exposed groups than the control groups. Similarly, when the concentrations of ethyl linoleate in meconium were grouped (trichotomized), there was a significant linear by linear association between alcohol exposure and group concentrations of ethyl linoleate (p=0.013). Furthermore, only alcohol-exposed infants were found in the group with the highest ethyl linoleate concentration. The sensitivity of ethyl linoleate in detecting prenatal alcohol exposure was only 26.9%, and its specificity and positive predictive value were 96.8 and 96.2%, respectively. There was no significant correlation between the concentration of ethyl linoleate in meconium and absolute alcohol consumed (oz) per drinking day across pregnancy, although a trend toward a positive correlation is seen at lower amounts of alcohol consumed. Among the polyunsaturated, long-chain FAEEs, there was weak evidence that the incidence (21.5% vs 6.5%, p=0.057) and concentration (p=0.064) of ethyl arachidonate (AA) were significantly higher in the alcohol-exposed groups than the control groups. Ethyl linolenate and ethyl docosahexanoate (DHA) in meconium were found only in the alcohol group, although not at statistically significant levels. Highly significant correlations were found among the concentrations of ethyl linoleate, ethyl linolenate, ethyl AA, and ethyl DHA in meconium (correlations ranged between rs=0.203, p=0.024; and rs=0.594, p<0.001). Conclusion: We conclude that FAEEs in meconium, particularly ethyl linoleate and ethyl AA, are biomarkers of high specificity for prenatal exposure to alcohol in newborn infants. We also propose that ethyl AA and DHA could be potential biomarkers of fetal alcohol effects on the developing fetal brain and should be investigated further. [source] Simplified scintigraphic methods for measuring gastrointestinal transit timesCLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, Issue 4 2000Graff To investigate whether simple transit measurements based on scintigraphy performed only 0, 2, 4 and 24 h after intake of a radiolabelled meal can be used to predict the mean transit time values for the stomach, the small intestine, and the colon, a study was conducted in 16 healthy volunteers. After ingestion of a meal containing 111indium-labelled water and 99mtechnetium-labelled omelette, imaging was performed at intervals of 30 min until all radioactivity was located in the colon and henceforth at intervals of 24 h until all radioactivity had cleared from the colon. Gastric, small intestinal and colonic mean transit times were calculated for both markers and compared with fractional gastric emptying at 2 h, fractional colonic filling at 4 h, and geometric centre of colonic content at 24 h, respectively. Highly significant correlations were found between gastric mean transit time and fractional gastric emptying at 2 h (111In: r=0·95, P<0·00001; 99mTc: r=0·96, P<0·00001), between small intestinal mean transit time and fractional colonic filling at 4 h (111In: r=,0·97, P<0·00001; 99mTc: r=,0·89, P<0·00001), and between colonic mean transit time and geometric centre of colonic content at 24 h (111In: r=, 0·88, P<0·00001). We therefore conclude that reliable regional gastrointestinal transit times can be estimated from scintigraphic images taken 0, 2, 4 and 24 h after intake of radiolabelled markers. [source] Sensitivity and reproducibility of indirect calorimetry in measurement of resting metabolic rateDRUG DEVELOPMENT RESEARCH, Issue 8 2008Cecilia Karlsson Abstract The aim of this study was to assess indirect calorimetry measurement of resting metabolic rate (RMR) with respect to sensitivity and reproducibility in a human study population suitable for early clinical studies to evaluate new anti-obesity candidate drugs. Twenty-four overweight, but otherwise healthy males were included in this randomized, single-blind, placebo-controlled, crossover study. Three different doses of epinephrine (0.005, 0.01, 0.03,µg · kg fat-free mass (FFM),1 · min,1) were used as active treatment. There were two identical study periods, separated by a 4-week washout. Increases in RMR were seen with all tested concentrations of epinephrine when compared with placebo. Changes in RMR of ,1.8% could be detected with 90% power in this crossover study design. The RMR values measured at the two study periods revealed a highly significant correlation (Spearman correlation 0.803, P=0.0007). To conclude, indirect calorimetry is a sensitive and robust means of measuring RMR. The method can be used to assess RMR in diverse clinical settings, even when considering modest differences. Drug Dev Res 69: 2008. © 2008 Wiley-Liss, Inc. [source] Effects of eight polycyclic aromatic compounds on the survival and reproduction of the springtail Folsomia fimetaria L. (collembola, isotomidae)ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 6 2001Line E. Sverdrup Abstract The effects of eight polycyclic aromatic compounds on the survival and reproduction of the collembolan Folsomia fimetaria L. were investigated in a well-characterized Danish agricultural soil. With the exception of acridine, polycyclic aromatic hydrocarbons (PAHs) and neutral N-, S-, and O-monosubstituted analogues showed similar toxicities to soil collembolans when the results were expressed in relation to total soil concentrations (mg/kg). The estimated concentrations resulting in a 10% reduction of reproductive output (EC10 values) were based on measured initial concentrations and were for acridine 290 mg/kg, carbazole 10 mg/kg, dibenzofuran 19 mg/kg, dibenzothiophene 7.8 mg/kg, fluoranthene 37 mg/kg, fluorene 7.7 mg/kg, phenantrene 23 mg/kg, and pyrene 10 mg/kg. When the EC10 values were converted to soil pore-water concentrations, they showed a highly significant correlation (r2 = 0.71, p < 0.01) to no-observed-effect concentrations for the freshwater crustacean Daphnia magna, as estimated by a quantitative structure activity relation (QSAR) for baseline toxicity (nonpolar narcosis). Only carbazole and acridine were more than two times more toxic (4.9 and 3.1, respectively) than expected from the Daphnia QSAR data. The latter result indicates that the toxicity of the tested substances is close to that expected for compounds with nonpolar narcosis as the mode of action. However, the relatively large uncertainties in the extrapolation method prevent final conclusions from being drawn. [source] Intralesional bovine papillomavirus DNA loads reflect severity of equine sarcoid diseaseEQUINE VETERINARY JOURNAL, Issue 4 2010R. HARALAMBUS Summary Reasons for performing study: Sarcoids are nonmetastasising, yet locally aggressive skin tumours that constitute the most frequent neoplasm in equids. Infection by bovine papillomaviruses types 1 and 2 (BPV-1, BPV-2) has been recognised as major causative factor in sarcoid pathogenesis, but a possible correlation of intralesional virus load with disease severity has not been established thus far. Hypothesis: Given the pathogenic role of BPV-1 and BPV-2 in sarcoid disease, we suggest that intralesional viral DNA concentration may reflect the degree of affection. Methods: Severity of disease was addressed by recording the tumour growth kinetics, lesion number and tumour type for 37 sarcoid-bearing horses and one donkey. Viral load was estimated via quantitative real-time PCR (qPCR) of the E2, E5, L1 and L2 genes from the BPV-1/-2 genome for one randomly selected lesion per horse and correlated with disease severity. Results: Quantitative PCR against E2 identified viral DNA concentrations ranging from 0,556 copies/tumour cell. Of 16 horses affected by quiescent, slowly growing single tumours or multiple mild-type lesions, 15 showed a viral load up to 1.4 copies per cell. In stark contrast, all equids (22/22) bearing rapidly growing and/or multiple aggressive sarcoids had a viral load between 3 and 569 copies per cell. Consistent results were obtained with qPCR against E5, L1 and L2. Conclusions: While tumours of the same clinical type carried variable virus load, confirming that viral titre does not determine clinical appearance, we identified a highly significant correlation between intralesional viral load and disease severity. Potential relevance: The rapid determination of BPV viral load will give a reliable marker for disease severity and may also be considered when establishing a therapeutic strategy. [source] Variable expression of CYP and Pgp genes in the human small intestineEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 6 2003M. Lindell Abstract Background ,The small intestine is receiving increased attention for its importance in drug metabolism. However, knowledge of the intervariability and regulation of the enzymes involved, cytochrome P450 and P-Glycoproteins (CYP and Pgp), is poor when compared with the corresponding hepatic enzymes. Methods ,The expression of eight different CYP genes and the Pgp were determined by reverse transcription polymerase chain reaction (RT-PCR) in 51 human duodenum biopsies. And the variability and correlation of expression was analyzed. Results ,Extensive interindividual variability was found in the expression of most of the genes. Only CYP2C9, CYP3A4 and Pgp were found in all samples. CYP1A2, CYP2A6 and CYP2E1 exhibited the highest interindividual variability. No strong correlation of expression existed between the genes. But a highly significant correlation was found between CYP2D6/1A2, 2D6/2E1, 1A2/2E1 and 2B6/2C9. Acetylsalicylic acid and omeprazole significantly increased the expression of CYPs 2A6, 2E1 and 3A4, respectively. Conclusions ,Extensive interindividual variability is characteristic for the expression of drug-metabolizing CYP and Pgp genes in human duodenum, and external factors such as drugs may further increase the variability. It is possible that the large interindividual variability may lead to variable bioavailability of orally used drugs and hence complicate optimal drug therapy, especially for drugs with a small therapeutic window. Elucidation of factors contributing to clinically important variances warrants further investigation. [source] REM sleep enhancement induced by different procedures improves memory retention in ratsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 9 2003Wolfram Wetzel Abstract Growing evidence supports the idea that sleep following learning is critically involved in memory formation. Recent studies suggest that information acquired during waking is reactivated and possibly consolidated during subsequent sleep, especially during rapid-eye movement (REM) or paradoxical sleep (PS). Critical reviews, however, have questioned PS and memory relationships, particularly because of shortcomings of the PS deprivation paradigm applied in many studies. Therefore, in the present study we used an opposite strategy, i.e. we investigated the effects of PS enhancement on memory retention. In three experiments, we found that selective PS enhancement, induced by different procedures after discrimination training in rats, results in increased retention tested 24 h later. Moreover, calculated in all animals (n = 61), there was a highly significant correlation between post-training PS values and retention scores. Our results suggest that an experimentally induced increase of PS after learning facilitates memory consolidation. [source] PLANT COLONIZATION IN CONDESA NIVATION HOLLOW, SIERRA DE GUADARRAMA (SPANISH CENTRAL SYSTEM)GEOGRAFISKA ANNALER SERIES A: PHYSICAL GEOGRAPHY, Issue 3 2009JULIO MUŃOZ JIMÉNEZ ABSTRACT. The purpose of this study was to determine plant distribution at a nivation hollow located in a Mediterranean high mountain area and to analyse the effects of snow cover, wind exposure, proximity to moisture and the characteristics of the substrate on the vegetation. We analyse these factors and interpret concurrent effects due to recent climate change. The nivation hollow, called Ventisquero de la Condesa, is located at 2258 m a.s.l., 40°47,10,N and 3°58,35,W, in the Sierra de Guadarrama (Madrid, Spain). We established 579 small sample plots in the study area, and grouped them into 29 transects where snow duration, wind exposure, availability of meltwater, geomorphologic instability and surface rockiness were examined directly and indirectly. The types of plants and the number of individuals per species were registered for each plot to establish ecological affinities among the 28 distinguishable species. Six showed the highest level of chionophily while nine showed the lowest adaptation to snow cover duration. A statistical study incorporating other variables applied in the research revealed that wind exposure, moisture capture and the intensity of geomorphologic dynamics have a highly significant correlation with nivation, while surface rockiness is a virtually independent factor. Due to environmental changes caused by recent global warming, several plant species, especially adapted to survival in snow conditions, coexist in the hollow with saxicolous plants that have invaded the site from adjacent grass and shrublands. [source] Tear-film lipid layer morphology and corneal sensation in the development of blinking in neonates and infantsJOURNAL OF ANATOMY, Issue 3 2005John G. Lawrenson Abstract The aim of the study was to evaluate the role of lipid layer thickness and corneal sensation in the development of blinking in neonates. The study group comprised sixty-four neonates and infants (mean age 27.5 ± 15 (sd) weeks, range 3.4,52) whose mothers were attending a general practice healthy baby clinic. Spontaneous eye-blink activity was determined from digital videographic recordings; tear film lipid layer morphology wasexamined using interference patterns produced by the Keeler TearscopeÔ Plus over a five-point grading scale (higher grades are associated with thick and stable lipid films); corneal sensation threshold was assessed with the Non-Contact Corneal Aesthesiometer (NCCA), using the eye-blink response as an objective indication that the cooling stimulus had been felt; palpebral aperture dimensions were measured using calibrated digital still images of the eye in the primary position. The overall mean spontaneous blink-rate was found to be 3.6 (± 0.3) blinks min,1, and the mean interblink time was 21.6 (± 2.8) s. The lowest blink-rates were observed in the 0,17-week age group (average 2 blinks min,1). The blink-rate showed a highly significant correlation with age (r = 0.46, P < 0.01). The overall mean lipid layer grading was 3.6 (± 0.2 SE) arbitrary units. Higher grades were found in the newborn and the mean grading score reduced with age (P < 0.01). The mean sensation threshold to blink (TTB) was 0.69 (0.04 SE) mbar, which did not differ from a control group of older subjects (P > 0.05). There was a rapid increase in palpebral aperture length and width from birth to 1 year old, with surface area increasing by 50% over the same period. We concluded that the low rate of spontaneous eye blink activity in neonates is associated with a thick stable lipid layer that may be a function of a small palpebral aperture. Furthermore, neonates appear to have the capacity to detect ocular surface cooling, which is a major trigger for spontaneous blinking. [source] An evaluation of monitoring possibilities of argatroban using rotational thromboelastometry and activated partial thromboplastin timeACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 1 2010M. ENGSTRÖM Background: Rotational thrombelastometry/thrombelastography with ROTEM® and TEG® is becoming available bedside in an increasing number of intensive care units, where many patients with heparin-induced thrombocytopenia (HIT) are treated. The study has been performed in an effort to find out whether ROTEM® could be an alternative to activated partial thromboplastin time (aPTT) when argatroban is used for anticoagulation. Methods: Argatroban was added in vitro to a series of citrated whole-blood samples from 10 healthy volunteers to obtain whole-blood concentrations of 0, 0.125, 0.25, 0.5, 1.0, 2.0, 4.0 and 8.0 mg/l. ROTEM® and whole-blood aPTT analyses were performed at each argatroban concentration. Correlation analyses were performed using the Spearman correlation analysis. Results: There was a significant and strong correlation between argatroban concentrations and clotting time (CT in ROTEM® analysis with INTEM) (P<0.0001 and r=0.98). Also, the ROTEM® time to maximum clot formation velocity (MAXV-t) appeared to have a very strong and highly significant correlation to argatroban concentrations (P<0.0001 and r=0.95). When we studied the correlation between aPTT and CT, we found a highly significant and strong correlation between these two analyses (P<0.0001 and r=0.97), especially so in the clinically relevant therapeutic range up to 100 s aPTT prolongation for HIT patients. Conclusion: A significant and strong correlation was found between argatroban concentrations and several ROTEM® parameters. Rotational thrombelastometry/thrombelastography has a potential role in increasing the safety of argatroban anticoagulation in critically ill patients. [source] Large-volume leukapheresis using femoral venous access for harvesting peripheral blood stem cells with the Fenwal CS 3000 Plus from normal healthy donors: Predictors of CD34+ cell yield and collection efficiencyJOURNAL OF CLINICAL APHERESIS, Issue 1 2003Sang Kyun Sohn Abstract The current paper reports on the predicting factors associated with satisfactory peripheral blood stem cell collection and the efficacy of large-volume leukapheresis (LVL) using femoral vein catheterization to harvest PBSCs with Fenwal CS 3000 Plus from normal healthy donors for allogeneic transplantation. A total of 113 apheresis procedures in 57 patients were performed. The median number of MNCs, CD3+ cells, and CD34+ cells harvested per apheresis was 5.3 × 108/kg (range, 0.3,11.0 × 108/kg), 3.0 × 108/kg (range, 0.2,6.6 × 108/kg), and 7.9 × 106/kg (range, 0.1,188.9 × 106/kg), respectively. The median collection efficiency of MNCs and CD34+ cells was 49.8% and 49.7%, respectively. A highly significant correlation was found between the collected CD34+ cell counts and the pre-apheresis WBC counts in the donors (P = 0.013), and between the collected CD34+ cell counts and the pre-apheresis peripheral blood (PB) CD34+ cell counts (P<0.001). Harvesting at least >4 × 106/kg CD34+ cells from the 1st LVL was achieved in 44 (77.2%) out of 57 donors and in 19 (90.5%) out of 21 donors with a PB-CD34+ cell count of >40/,l. There was no significant difference in the harvested MNC and CD34+ cell counts between the 1st and 2nd apheresis. The catheter-related complications included catheter obstruction (n = 2) and hematoma at the insertion site (n = 3). Accordingly, LVL using femoral venous access for allogeneic PBSC collection from normal healthy donors would appear to be safe and effective. J. Clin. Apheresis 18:10,15, 2003. © 2003 Wiley-Liss, Inc. [source] Comparison of relative forced expiratory volume of one second with dynamic magnetic resonance imaging parameters in healthy subjects and patients with lung cancer,JOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 3 2005Christian Plathow MD Abstract Purpose To assess relative forced expiratory volume in one second (FEV1/vital capacity (VC)) in healthy subjects and patients with a lung tumor using dynamic magnetic resonance imaging (dMRI) parameters. Materials and Methods In 15 healthy volunteers and 31 patients with a non-small-cell lung carcinoma stage I (NSCLC I), diaphragmatic length change (LE1) and craniocaudal (CC) intrathoracic distance change within one second from maximal inspiration (DE1) were divided by total length change (LEtotal, DEtotal) as a surrogate of spirometric FEV1/VC using a true fast imaging with steady-state precession (trueFISP) sequence (TE/TR = 1.7/37.3 msec, temporal resolution = 3 images/second). Influence of tumor localization was examined. Results In healthy volunteers FEV1/VC showed a highly significant correlation with LE1/LEtotal and DE1/DEtotal (r > 0.9, P < 0.01). In stage IB tumor patients, comparing tumor-bearing with the non-tumor-bearing hemithorax, there was a significant difference in tumors of the middle (LE1/LEtotal = 0.63 ± 0.05 vs. 0.73 ± 0.04, DE1/DEtotal = 0.66 ± 0.05 vs. 0.72 ± 0.04; P < 0.05) and lower (P < 0.05) lung region. Stage IA tumor patients showed no significant differences with regard to healthy subjects. Conclusion dMRI is a simple noninvasive method to locally determine LE1/LEtotal and DE1/DEtotal as a surrogate of FEV1/VC in volunteers and patients. Tumors of the middle and lower lung regions have a significant influence on these MRI parameters. J. Magn. Reson. Imaging 2005;21:212,218. © 2005 Wiley-Liss, Inc. [source] Diffusion technique for 15N and inorganic N analysis of low-N aqueous solutions and Kjeldahl digests,RAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 11 2008Rui Rui Chen Diffusion of ammonia is a common sample preparation method for the stable isotope analysis of inorganic nitrogen in aqueous solution. Classical diffusion methods usually require 6,12 days of diffusion and often focus on 15N/14N analysis only. More recent studies have discussed whether complete N recovery was necessary for the precise analysis of stable N isotope ratios. In this paper we present a newly revised diffusion technique that allows correct and simultaneous determination of total N and 15N at% from aqueous solutions and Kjeldahl digests, with N concentrations down to sub-0.5-mg,N,L,1 levels, and it is tested under different conditions of 15N isotope labelling. With the modification described, the diffusion time was reduced to 72,h, while the ratios of measured and expected 15N at% were greater than 99% and the simultaneous recovery of total N was >95%. Analysis of soil microbial biomass N and its 15N/14N ratio is one of the most important applications of this diffusion technique. An experiment with soil extracts spiked with 15N-labelled yeast showed that predigestion was necessary to prevent serious N loss during Kjeldahl digestion of aqueous samples (i.e. soil extracts). The whole method of soil microbial biomass N preparation for 15N/14N analysis included chloroform fumigation, predigestion, Kjeldahl digestion and diffusion. An experiment with soil spiked with 15N-labelled yeast was carried out to evaluate the method. Results showed a highly significant correlation of recovered and added N, with the same recovery rate (0.21) of both total N and 15N. A kN value of 0.25 was obtained based on the data. In conclusion, the diffusion method works for soil extracts and microbial biomass N determination and hence could be useful in many types of soil/water studies. Copyright © 2008 John Wiley & Sons, Ltd. [source] Prognostic Indicators of Occult Metastases in Oral CancerTHE LARYNGOSCOPE, Issue 7 2002Mario Russolo MD Abstract Objective We evaluated the importance of several tumor factors related to predicting the presence of occult metastases in the oral cavity. Study Design Retrospective case study. Methods The study comprises 29 patients treated at the Department of Otorhinolaryngology (University of Trieste, Cattinara Hospital, Trieste, Italy) between January 1990 and December 2000, who had T1-T2 carcinoma of the oral cavity that had or had not extended to the oropharynx and were clinically evaluated as N0 neck. The patients all underwent surgery with removal of tumor and neck dissection. Four tumor-related parameters were examined with the aim of evaluating their predictivity of metastasis: tumor class, degree of keratinization, degree of differentiation according to Brooler's histopathological grading, and invasive cell grading (ICG). With the exception of tumor class, these parameters were evaluated both in the biopsy and in the surgical specimen and the findings were then compared. We evaluated existing correlations between each individual parameter and the histopathological presence of micrometastases (pN+) and extracapsular spread revealed when specimens from the neck were examined. Results There was a highly significant correlation between ICG equal to or greater than 13 (range, 5,20) and the presence of occult metastases (P = .0017). On the basis of our findings, the ICG parameter correctly identified 9 of 10 (pN+) patients and could have reduced overtreatment from 65.5% to 17.2% in histopathologically negative necks (pN0). Conclusion It would appear that with a delay in programming a neck dissection so as to consider ICG in combination with thickness, as in seven recent patients, identification of locoregional occult metastases (pN+) might be more precise. [source] Correlation Between Decreased Type-II Interleukin-1 Receptor and Increased Monocyte Chemotactic Protein-1 Expression in the Endometrium of Women with EndometriosisAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 4 2001ABDELAZIZ KHARFI PROBLEM: Monocyte chemotactic protein-1 (MCP-1), a potent inducer of macrophage recruitment and activation, is overexpressed in the eutopic endometrium of women with endometriosis. Eutopic endometrial cells of women with endometriosis secrete higher levels of MCP-1 than those of normal women, following stimulation with interleukin-1 (IL-1). The aim of this study was to examine whether there is any correlation between the expression of IL-1 receptor type II (IL-1RII), a specific downregulator of IL-1 activity, and that of MCP-1 in the eutopic endometrium of women with endometriosis. METHOD OF STUDY: Endometrial biopsies of 46 women with endometriosis and 22 healthy women were evaluated simultaneously for IL-1RII and MCP-1 expression by immunohistochemistry. RESULTS: Our study revealed a highly significant correlation between the decreased expression of IL-1RII and the increased expression of MCP-1 in the endometrial tissue of women with endometriosis (Spearman correlation coefficient r=,0.377, P=0.002), particularly in the initial stages of the disease (stages I and II; r=,0.368, P=0.020 and r=,0.480, P=0.002, respectively). Furthermore, this correlation was observed in the proliferative (r=,0.366, P=0.047) and the secretory phases (r=,0.321, P=0.049) of the menstrual cycle. CONCLUSIONS: These results suggest that the reduced capability of endometrial tissue to downregulate IL-1 proinflammatory effects may be involved in the increased expression of MCP-1 in the endometrium of women with endometriosis and the establishment of an inflammatory state. The results also indicate a sustained process of cell activation throughout the menstrual cycle. [source] Geographically dependent distribution of gyrA gene mutations at codons 83 and 87 in Salmonella Hadar, and a novel codon 81 Gly to His mutation in Salmonella EnteritidisAPMIS, Issue 3 2004B. A. LINDSTEDT In all, 90 nalidixic acid-resistant clinical strains of Salmonella Hadar and Salmonella Enteritidis isolated in Norway but of predominantly foreign origin were subjected to sequencing of the gyrA, gyrB, parC and parE genes. All the isolates contained at least one mutation in gyrA codon 83 or codon 87. A highly significant correlation between mutations in gyrA codon 83 and strains originating from Southeast Asia was found in S. Hadar but not in S. Enteritidis. A novel gyrA codon 81 Gly to His mutation was discovered in one S. Enteritidis isolate. One amino-acid (aa) changing mutation was found outside the quinolone resistance-determining region (QRDR) of S. Hadar parC at codon 57, which has previously only been observed once in Salmonellae. [source] The prevalence and clinical characteristics of pruritus among patients with extensive psoriasisBRITISH JOURNAL OF DERMATOLOGY, Issue 5 2000G. Yosipovitch Background,Many patients with psoriasis are known to suffer from itch. However, the data available regarding itch and its characteristics in psoriasis are sparse. Objectives,To examine the prevalence of pruritus and various related clinical characteristics in 101 patients with extensive psoriasis. Methods,A structured questionnaire was used. Results,Generalized pruritus was a feature of psoriasis in 84% of the patients. In 77% of these it appeared on a daily basis. It involved all areas of the body, had prolonged duration and appeared mainly in the evening and at night. The pruritus significantly affected quality of life. Important daily factors that were found to exacerbate the itch were ambient heat (81%), skin dryness (80%), sweating (65%) and stress (55%). Important factors that were found to ameliorate itch were sleep (57%) and cold showers (55%). The pruritus was found to be unresponsive to most available antipruritics, including phototherapy. Itch intensity as reflected by a visual analogue scale did not correlate with Psoriasis Area and Severity Index scores; however, a highly significant correlation was obtained between the affective descriptors and itch intensity in the worst itch states (r = 0·6, P < 0·001). Conclusions,Pruritus is a common feature of psoriasis and affects quality of life. [source] Assessment of surgical competence at carotid endarterectomy under local anaesthesia in a simulated operating theatre,BRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 4 2010S. A. Black Background: Methods of surgical training that do not put patients at risk are desirable. A high-fidelity simulation of carotid endarterectomy under local anaesthesia was tested as a tool for assessment of vascular surgical competence, as an adjunct to training. Methods: Sixty procedures were performed by 30 vascular surgeons (ten junior trainees, ten senior trainees and ten consultants) in a simulated operating theatre. Each performed in a non-crisis scenario followed by a crisis scenario. Performance was assessed live by means of rating scales for technical and non-technical skills. Results: There was a significant difference in technical skills with ascending grade for both generic and procedure-specific technical skill scores in both scenarios (P < 0·001 for all comparisons). Similarly, there was also a significant difference in non-technical skill with ascending grade for both scenarios (P < 0·001). There was a highly significant correlation between technical and non-technical performance in both scenarios (non-crisis: rs = 0·80, P < 0·001; crisis: rs = 0·85, P < 0·001). Inter-rater reliability was high (,, 0·80 for all scales). Conclusion: High-fidelity simulation offers competency-based assessment for all grades and may provide a useful training environment for junior trainees and more experienced surgeons. Copyright © 2010 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd. [source] Maternal plasma level of antimicrobial peptide LL37 is a major determinant factor of neonatal plasma LL37 levelACTA PAEDIATRICA, Issue 6 2010A Mandic Havelka Abstract Aim:, To determine cathelicidin antimicrobial peptide LL37subcellular distribution in cord neutrophils and normal plasma LL37 levels in mothers and neonates, relate them to delivery mode and relevant biochemical markers, including 25-OHvitamin D [25(OH)D] as this molecules increases cathelicidin gene expression. Methods:, A total of 115 infants were included, n = 68 with normal delivery and n = 47 with elective Caesarean section (C-section), a subset of these being 50 mother,infant pairs. Biomarkers were determined in maternal and cord blood. Subcellular peptide LL37 distribution was analysed with immunoelectron microscopy. Results:, Cord plasma LL37 levels were three-times higher after normal delivery compared with C-section. A highly significant correlation was observed between maternal and cord plasma LL37 levels, regardless of delivery mode. No relationship was found between LL37 and 25(OH)D levels. Neutrophils from cord blood after normal delivery contained 10-times more cytoplasmatic cathelicidin peptide compared with corresponding cells after C-section where a strict granular localization was found. Conclusion:, These data are consistent with a placental transfer of LL37 and identifies maternal stores as the critical factor determining neonatal plasma LL37 level. An additional enhancement of neonatal cathelicidin mobilization and release is connected to normal delivery stress. [source] Malformation of True Bug (Heteroptera): a Phenotype Field Study on the Possible Influence of Artificial Low-Level RadioactivityCHEMISTRY & BIODIVERSITY, Issue 4 2008Cornelia Hesse-Honegger Abstract The results of extensive field studies on the malformation of Western European true bugs (Heteroptera) are reviewed. More than 16,000 individuals were collected over two decades, and subjected to detailed visual inspection. Various types of disturbances were found and illustrated in detail. Depending on country, region, as well as local influences, severe disturbances and high degrees of malformation were noticed, especially in the sphere of nuclear-power installations in Switzerland (Aargau), France (La Hague), and Germany (Gundremmingen). Malformation reached values as high as 22 and 30% for morphological (MD) and total disturbance (TD), respectively. This is far above the values expected for natural populations (ca. 1%) or those determined for true bugs living in biotopes considered as relatively ,intact' (1,3%). A detailed chi-square test of the malformation data obtained for 650 true bugs from 13 collection sites near the nuclear-reprocessing plant La Hague showed a highly significant correlation (p=0.003) between malformation and wind exposure/local topography. Similar observations were made for other study sites. Currently, our data are best rationalized by assuming a direct influence between the release of anthropogenic radionuclides such as tritium (3H), carbon-14 (14C), or iodine-131 (131I), constantly emitted by nuclear-power and nuclear-reprocessing plants, as well as by Chernobyl and bomb-testing fallout, which is rich in caesium-137 (137Cs) and other long-lived noxious isotopes that have entered the food chain. The present work supports the growing evidence that low-level radiation, especially in the form of randomly scattered ,hot' , - and , -particles, mainly transported via aerosols, puts a heavy burden on the biosphere in general, and on true bugs in particular. These insects could, thus, serve as sensitive ,bio-indicators' for future studies. [source] Multiple cytokines in human tear specimens in seasonal and chronic allergic eye disease and in conjunctival fibroblast culturesCLINICAL & EXPERIMENTAL ALLERGY, Issue 6 2006A. Leonardi Summary Background Several cytokines are involved in the recruitment and activation of inflammatory cells in ocular allergic diseases. The purpose of the study was to assay multiple cytokines and chemokines in tears, to compare subgroups of allergic conjunctivitis (AC) with controls, and in culture supernatants to determine whether conjunctival fibroblasts produce some of these cytokines. Methods Fifty to one hundred microlitre tears were obtained from patients with active seasonal allergic conjunctivitis (SAC; n=12), vernal keratoconjunctivitis (VKC; n=18), atopic keratoconjunctivitis (AKC; n=6) and non-atopic controls (n=14). Primary conjunctival fibroblasts grown in vitro were stimulated with IL-4, IL-13 or TNF-, for 24 h. Cell-free tear and culture supernatants were assayed for IL-1,, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12, IL-13, IFN-,, TNF-,, eotaxin, MCP-1 and RANTES using multiplex bead analysis. Induction of chemokine gene expression was determined by PCR. Results IL-1,, IL-2, IL-5, IL-6, IL-12, IL-13, MCP-1 were increased in all tears groups compared with controls, with highly significant correlations between many of these molecules. In addition IL-4, IFN-,, and IL-10 were elevated in SAC and VKC, while eotaxin and TNF-, were only increased in VKC. IL-6, IL-8, MCP-1, RANTES and eotaxin were detected from fibroblasts cultures, and were all up-regulated by TNF-,. By PCR, fibroblasts expressed MCP-1 transcripts constitutively, whereas IP-10 and Mig were up-regulated by TNF-,. Conclusions Differential cytokine levels support tears as a useful indicator of immune mechanisms occurring during AC. The striking similarities in chemokine profiles between tears and fibroblasts suggest these cells as likely sources of chemokines in tears. [source] | |||||||||||||||||||